The compounds covered below are selective kappa opioid agonists. These compounds and their salts are useful in the treatment of arthritis, hypertension, pain, particularly pain which is inflammatory in origin and post-operative pain, inflammation, migraine, inflammatory disorders of the gastrointestinal tract, Parkinsonism, and stroke.
These compounds with the (S)-hydroxyl group on the 3 position of the pyrrolidine ring are more potent kappa agonists in the rabbit vas deferens assay than those compounds lacking a hydroxyl and should, therefore, be more potent for the treatment of the above mentioned conditions.